Changed ImGui::GetTime() return value from float to double to avoid accumulating floating point imprecisions over time.

CHANGELOG.txt

@@ -38,6 +38,7 @@ Breaking Changes:
  - Removed per-window ImGuiWindowFlags_ResizeFromAnySide beta flag in favor `io.OptResizeWindowsFromEdges=true` to enable the feature globally. (#1495)
    The feature is not currently enabled by default because it is not satisfying enough.
  - Style: Renamed ImGuiCol_ModalWindowDarkening to ImGuiCol_ModalWindowDimBg for consistency with other features. Kept redirection enum (will obsolete).
+ - Changed ImGui::GetTime() return value from float to double to avoid accumulating floating point imprecisions over time.
 
 Other Changes:
 

imgui.cpp

@@ -190,7 +190,7 @@
         io.MouseDown[1] = my_mouse_buttons[1];
 
         // Call NewFrame(), after this point you can use ImGui::* functions anytime
-        // (So you want to try calling Newframe() as early as you can in your mainloop to be able to use imgui everywhere)
+        // (So you want to try calling NewFrame() as early as you can in your mainloop to be able to use imgui everywhere)
         ImGui::NewFrame();
 
         // Most of your application code here
@@ -305,6 +305,7 @@
  When you are not sure about a old symbol or function name, try using the Search/Find function of your IDE to look for comments or references in all imgui files.
  You can read releases logs https://github.com/ocornut/imgui/releases for more details.
 
+ - 2017/07/22 (1.63) - changed ImGui::GetTime() return value from float to double to avoid accumulating floating point imprecisions over time.
  - 2018/07/08 (1.63) - style: renamed ImGuiCol_ModalWindowDarkening to ImGuiCol_ModalWindowDimBg for consistency with other features. Kept redirection enum (will obsolete).
  - 2018/07/06 (1.63) - removed per-window ImGuiWindowFlags_ResizeFromAnySide beta flag in favor of a global io.OptResizeWindowsFromEdges to enable the feature.
  - 2018/06/06 (1.62) - renamed GetGlyphRangesChinese() to GetGlyphRangesChineseFull() to distinguish other variants and discourage using the full set.
@@ -2907,7 +2908,7 @@ ImDrawData* ImGui::GetDrawData()
     return g.DrawData.Valid ? &g.DrawData : NULL;
 }
 
-float ImGui::GetTime()
+double ImGui::GetTime()
 {
     return GImGui->Time;
 }
@@ -3667,7 +3668,7 @@ static void ImGui::UpdateMouseInputs()
         g.IO.MouseDoubleClicked[i] = false;
         if (g.IO.MouseClicked[i])
         {
-            if (g.Time - g.IO.MouseClickedTime[i] < g.IO.MouseDoubleClickTime)
+            if ((float)(g.Time - g.IO.MouseClickedTime[i]) < g.IO.MouseDoubleClickTime)
             {
                 ImVec2 delta_from_click_pos = IsMousePosValid(&g.IO.MousePos) ? (g.IO.MousePos - g.IO.MouseClickedPos[i]) : ImVec2(0.0f, 0.0f);
                 if (ImLengthSqr(delta_from_click_pos) < g.IO.MouseDoubleClickMaxDist * g.IO.MouseDoubleClickMaxDist)
@@ -3808,6 +3809,7 @@ void ImGui::NewFrame()
     g.TooltipOverrideCount = 0;
     g.WindowsActiveCount = 0;
 
+    // Setup current font and draw list
     SetCurrentFont(GetDefaultFont());
     IM_ASSERT(g.Font->IsLoaded());
     g.DrawListSharedData.ClipRectFullscreen = ImVec4(0.0f, 0.0f, g.IO.DisplaySize.x, g.IO.DisplaySize.y);

imgui.h

@@ -525,7 +525,7 @@ namespace ImGui
     IMGUI_API void          SetItemAllowOverlap();                                              // allow last item to be overlapped by a subsequent item. sometimes useful with invisible buttons, selectables, etc. to catch unused area.
     IMGUI_API bool          IsRectVisible(const ImVec2& size);                                  // test if rectangle (of given size, starting from cursor position) is visible / not clipped.
     IMGUI_API bool          IsRectVisible(const ImVec2& rect_min, const ImVec2& rect_max);      // test if rectangle (in screen space) is visible / not clipped. to perform coarse clipping on user's side.
-    IMGUI_API float         GetTime();
+    IMGUI_API double        GetTime();
     IMGUI_API int           GetFrameCount();
     IMGUI_API ImDrawList*   GetOverlayDrawList();                                               // this draw list will be the last rendered one, useful to quickly draw overlays shapes/text
     IMGUI_API ImDrawListSharedData* GetDrawListSharedData();                                    // you may use this when creating your own ImDrawList instances
@@ -1162,7 +1162,7 @@ struct ImGuiIO
 
     ImVec2      MousePosPrev;               // Previous mouse position temporary storage (nb: not for public use, set to MousePos in NewFrame())
     ImVec2      MouseClickedPos[5];         // Position at time of clicking
-    float       MouseClickedTime[5];        // Time of last click (used to figure out double-click)
+    double      MouseClickedTime[5];        // Time of last click (used to figure out double-click)
     bool        MouseClicked[5];            // Mouse button went from !Down to Down
     bool        MouseDoubleClicked[5];      // Has mouse button been double-clicked?
     bool        MouseReleased[5];           // Mouse button went from Down to !Down

imgui_demo.cpp

@@ -819,7 +819,7 @@ void ImGui::ShowDemoWindow(bool* p_open)
             // Tip: If your float aren't contiguous but part of a structure, you can pass a pointer to your first float and the sizeof() of your structure in the Stride parameter.
             static float values[90] = { 0 };
             static int values_offset = 0;
-            static float refresh_time = 0.0f;
+            static double refresh_time = 0.0;
             if (!animate || refresh_time == 0.0f)
                 refresh_time = ImGui::GetTime();
             while (refresh_time < ImGui::GetTime()) // Create dummy data at fixed 60 hz rate for the demo
@@ -3020,8 +3020,8 @@ static void ShowExampleAppLog(bool* p_open)
     static ExampleAppLog log;
 
     // Demo: add random items (unless Ctrl is held)
-    static float last_time = -1.0f;
-    float time = ImGui::GetTime();
+    static double last_time = -1.0;
+    double time = ImGui::GetTime();
     if (time - last_time >= 0.20f && !ImGui::GetIO().KeyCtrl)
     {
         const char* random_words[] = { "system", "info", "warning", "error", "fatal", "notice", "log" };

imgui_internal.h

@@ -616,7 +616,7 @@ struct ImGuiContext
     float                   FontBaseSize;                       // (Shortcut) == IO.FontGlobalScale * Font->Scale * Font->FontSize. Base text height.
     ImDrawListSharedData    DrawListSharedData;
 
-    float                   Time;
+    double                  Time;
     int                     FrameCount;
     int                     FrameCountEnded;
     int                     FrameCountRendered;